This week in science – March 4

Eyewear that changes as your eyes do

A new type of eyeglass developed by startup company Adlens will allow users to change the prescription strength as their eyes change. Image courtesy Adlens

Our eyes naturally degrade as we get older. That’s why optometrists recommend yearly eye exams. So imagine a pair of glasses that could change as your eyes do without the need for new lenses.

Thanks to Adlens, a U.K.-based startup, that may become a reality.

The glasses, which are still in the research stage, have a dial on the side and a lens that is filled with a highly refractive liquid. Turning the dial will allow more liquid into the lenses which will alter the curvature of the lens, resulting in varying prescription strengths.

The product is primarily marketed towards developing countries, where the costs of buying new eyeglasses can be prohibitively high.

The water on Mars debate rages on

Evidence recovered from Martian meteor Yamato gives credence to the idea that at some point there was liquid on Mars. Tim Evanson/Flickr Commons

A team of scientists has discovered possible evidence pointing towards the past existence of water on Mars by examining a Martian asteroid on Earth.

The team of scientists, led by Lauren White of the NASA Jet Propulsion Laboratory, examined the asteroid Yamato, which was found on the Yamato glacier in Antarctica. The asteroid was dated to 1.3 billion years ago and contained tunnel structures and spherules between the layers of rock which are distinct from the surrounding layers.

Both these features are indicative of biotic decay which suggests that these features were caused by liquid alterations.

“While robotic missions to Mars continue to shed light on the planet’s history, the only samples from Mars available for study on Earth are Martian meteorites,” White said in a press release. “On Earth, we can utilize multiple analytical techniques to take a more in-depth look into meteorites and shed light on the history of Mars.”

A body shape index may provide a more accurate picture of health

A new study by researchers at City College in New York has revealed that for predicting mortality, a body shape index (ABSI) is a better indicator than body mass index (BMI).

ABSI is a measurement that takes into account height, weight and waist circumference. BMI only takes into account height and weight. The study looked at how increases in both ABSI and BMI affected mortality rates.

ABSI had a stronger correlation than BMI. Those in the top 20 per cent for ABSI had mortality rates 61 per cent higher than those in the bottom 20 per cent of ABSI. This makes ABSI a far better indicator of the risks associated with obesity than BMI.

You can find out your ABSI and how it compares to the average online at http://absi-calc.appspot.com/.